Patient transfer apparatus



Dec. 31, 1963 F. 0. LEE

PATIENT TRANSFER APPARATUS 6 Sheets-Sheet 1 Filed Oct. 4, 1960 Q Q INVENTOR.

Dec. 31, 1963 Filed 001;. 4, 1960 F. C. LEE

PATIENT TRANSFER APPARATUS 6 Sheets-Sheet 2 INVENTOR.

Dec. 31, 1963 F. c. LEE

PATIENT TRANSFER APPARATUS 6 Sheets-Sheet 3 Filed Oct. 4. 1960 INVENTOR. QM d [if Dec. 31, 1963 F. 0. LEE

PATIENT TRANSFER APPARATUS 6 SheetsSheet 4 Filed Oct. 4, 1960 NR .wR

Dec. 31, 1963 F. c. LEE

PATIENT TRANSFER APPARATUS 6 Sheets-Sheet 5 Filed Oct. 4, 1960 \& MV

Dec. 31, 1963 F. c. LEE 3,115,646

PATIENT TRANSFER APPARATUS Filed Oct. 4. 1960 6 Sheets-Sheet 6 INVEN TOR.

United States Patent 3,115,646 PATIENT TRANSFER APPARATUS Fred C. Lee, 3805 Ranch Top Road, Pasadena, Calif. Filed on. 4, 19611, Ser. No. 60,482 7 Claims. (Cl. l-51) The present invention relates to a method and apparatus for the transfer of a person, particularly a hospital patient or invalid, and an improved mattress for use in such transfer.

The transfer of patients in a hospital, or of invalids, is a well-known problem. Many attempts have been made to provide satisfactory methods for accomplishing such transfer and many different types of apparatus have been proposed for use in such transfer. However, despite the widespread attention which this problem has received, the standard method presently used for such transfer still consists of the manual lifting of the patient or invalid from the bed by attendants and the depositing of patient or invalid on what is known as a wheel stretcher. The patient or invalid is then wheeled on the wheel stretcher to his destination, whereupon the process is repeated in reverse, i.e., the patient is lifted by the attendants from the wheel stretcher and deposited on a second bed or operating table. In many instances, this repeated lifting of the patient has been proven detrimental to the patients well-being, particularly, if the patient has suffered back injuries or has recently undergone surgery. However, this system has remained in widespread use to the exclusion of other systems, since it was proved to be the only acceptable method for the transfer of such persons from place to place.

According to the present invention, a novel method is utilized for transferring hospital patients or invalids from place to place, which permits the patient or invalid to remain on the same mattress throughout his confinement. The method contemplates the insertion of a mattress support member under the mattress, so as to be between the mattress and the mattress support surface, and the removal of the mattress from the mattress support surface by means of this mattress support member. The mattress and support member are then disposed on a transfer frame. The transfer frame is moved to the destination of the person being transferred. Upon reaching the destination, the person is deposited on another bed or operating table or the like by a method which is the reverse of the method just described.

The novel apparatus for the practice of the invention includes a movable transfer frame which has a mattress support member disposed thereon and connected thereto, so as to be selectively laterally movable with respect thereto. Means are provided to selectively move the mattress support member laterally with respect to the transfer frame.

According to the presently preferred form of the invention, an improved mattress is to be utilized in conjunction with the practice of the invention. The improved mattress comprises a mattress body which has attaching means connected thereto. The attaching means are utilized to engage attaching means on the transfer frame during the insertion of the mattress support member under the mattress, thus holding the mattress in position on the bed mattress support surface.

The invention may be more readily understood by referring to the accompanying drawings in which:

FIGURE 1 is a side elevation of a transfer apparatus according to the present invention;

FIGURE 2 is a plan view of the transfer apparatus of FIG. 1;

FIGURE 3 is a perspective of the improved mattress of the present invention;

FIGURE 4 is an end view of the transfer apparatus of FIG. 1 connected to a mattress support surface, in which the mattress support member is in the process of being inserted under the mattress;

FIGURE 5 is a partial sectional view showing the detail of the means for selectively moving the support member laterally with respect to the transfer frame;

FIGURE 6 is a partial sectional view showing the actuating mechanism for the lateral movement of the support member with respect to the transfer frame;

FIGURE 7 is a sectional view of a clamp for the engagement of the mattress support surface with the transfer frame;

FIGURE 8 is a partial sectional view of the transfer frame illustrating the apparatus for fixing the vertical position and inclination of the support member;

FIGURE 9 is a partial plan view of the transfer frame showing in further detail the apparatus for selectively fixing the vertical position and inclination of the support member;

FEGURE 10 is a sectional view illustrating in detail the apparatus for normally fixing the support member parallel to the transfer frame; and

FIGURE 11 is a partial sectional view of an alternate embodiment of the mechanism for selectively laterally disposing the support member with respect to the transfer frame.

Referring now to P16. 1, there is shown a side elevation of the preferred embodiment of a transfer apparatus 1110 according to the invention. The transfer apparatus 1111? includes a transfer frame 191 and a support member 102. The support member 1% has leaves 1% which are illustrated in their upturned position. The leaves 103 are connected to a base 194 by means of hinges (not shown, see FIG. 2). Rotary lock assemblies 105 are utilizable to selectively lock the leaves 1193 in their upturned position. The lock assembies 105 are connected to a rectangular frame 1%, which is a portion of the transfer frame 101. The rectangular frame 196 is connected to a base frame 107 by means of a first attaching member 1118 and a second attaching member 1119. The first attaching member 1118 is attached to the frames 1% and 1117 by two pairs of pivots 110 and 111, and the second attaching member 1139 is attached to the frames 1% and 1117 by two pairs of pivots 112 and 113.

The attaching member 108 has an extension 115 which terminates in a threaded pivot 116. A threaded crank 117 extends through the threaded pivot 116 and is attached to the frame 107 by an attaching lock (not shown, see FIG. 8). The frame 197 terminates in four conventional lockable, rotatable wheels 1211 at opposite ends of the frame 1117. A second crank 118 extends through an attaching lock (not shown, see FIG. 9) and into a threaded positioning arm 119, which is pivotally connected to the arm 169.

The frame 1116 has attached thereto a lateral displacement assembly 125, which is operable to cause the support member 1112 to be displaced laterally with respect to the frame 1% when the lock assemblies 1115 are unlocked. The displacement assembly includes a crank 126, which is connected to a drive shaft 127. The drive shaft 127 extends into a gear box 128, from which extends a torque transfer tube 129. The torque transfer tube 129 terminates in a slave drive box 139.

Pairs of attaching clamps are attached to each side of the frame 166-. The clamps 135 have a clamp release mechanism 136, which includes a release arm 137 and a biasing spring 138. The release arm 137 terminates in a handle 139. A mattress connecting assembly 146 is disposed at either end of the frame 1116. The connecting assemblies 146' are adapted to be selectively raised and lowered with respect to the frame 1%.

FIGURE 2 illustrates the construction of one embodiment of the connecting assemblies 141) as having a hook 141 attached to a hook arm 14 2. The hook arm 142 is connected to a positioning body 143 having a set screw 144 therein which is utilizable to fix the lateral position of the arm 142. The arm 1 .2 terminates in a small ball 145, for the convenience of the operator. Obviously, other types of connecting assemblies can be used, and such alternate embodiments are Within the scope of the invention. A pair of connecting hinges 1% connect the leaves 1133 to the base 1114. The hinges 146 are preferably made of an electrically conductive material, so as to provide for electrical circuit continuity between the leaves 103 and base 1%. Otherwise, undesirable charges of static electricity may build up. The surface of the support member 1112 is of material with a low coefiicient of friction for facilitating the practice of the device. For example, tetrafluoroethylene can be used.

FIGURE 3 is a perspective view of a mattress to be utilized with the transfer apparatus 1% in the practice of the invention. The mattress includes a mattress body 151 partially covered by a fitted sheet 152. On a lower surface 153 of the mattress body 151, grommet attaching strips 154 are attached by any conventional means. For example, the grommet attaching strips 154 may be of fabric and may be sewn to the bottom surface 153, as indicated by the dotted lines 155. Each of the grommet attaching strips 154 terminates in a grommet 15s at either end thereof. The disposition of a grommet to either side of the mattress bottom 153 is preferable in order to provide for patient transfer from either the left or right side of a bed, as will subsequently become apparent. The

hooks 141 (FIG. 2) engage the grommets 156 to connect the mattress 150 to the frame 106.

FIGURE 4 is an end view of the transfer apparatus 195), a bed 152, which includes mattress 151 and a bed frame 169 having a lateral end support 161 upon which a bed mattress 1:12 rests. The bed 159 has vertical legs 163. An attaching bracket 165 is bolted to the horizontal frame members res by bolts 166. It will be noted that the bracket 165 engages the attaching clamp 155 so as to hold the transfer apparatus 1W fixed in position with respect to the bed frame 160. This is the preferred method for fixing the position of the transfer apparatus with respect to the bed frame 16%. However, other methods will be apparent for accomplishing such a fixing of the disposition of the transfer apparatus. For example, the wheels 1211 can be locked.

The connecting assembly is illustrated in its raised position and is shown to include, in addition to the parts previously mentioned, an attaching arm 17%, which extends between the positioning body and height positioning assembly 171. The height positioning assembly 171 includes a spring-loaded ball detent 172 extending through a main body portion 173 to engage the attaching arm 1711. As shown in FIG. 4, the support member 192, including leaves 163, is disposed over the rectangular frame 106, so as to ride upon four rollers 175 mounted on axles 176 which pass through support plates 177, associated with the lateral displacement assembly 125, and attached to the frame 1%.

In FIG. 5, a partial view of the lateral displacement assembly is shown. The lateral displacement assembly 125 includes a first gear 181 attached to the drive shaft 127. The first gear 180 engages a second gear 181 which is attached to the torque transfer tube 129. The second gear 181 has a cable winding drum (not shown, see FIG. 6) attached thereto, about which cables 182 and 183 are wound. Cable 132 is wound in a clockwise manner and extends accordingly from the cable drum to the left-hand side of the apparatus, as shown in FIG. 5. Cable 183 is wound counterclockwise, and extends from the right-hand side of the drum.

A cable tension assembly 1%, which includes a pivot 191 and a pivot arm 1&2, to which an idler wheel 1% is rotatably connected by an axle 194, is shown as having a tensioning spring 125 extending through an aperture 11% therein. The tensioning spring is connected to the opposite pivot arm 192 so as to exert a lateral tension on the pivot arms 192, thus urging the idler wheel 193 in a counterclockwise or downward direction. This urging maintains a tension on the cables 182 and 183.

The cable 182 passes about the rollers 175 so as to reverse its direction and extend to the right as shown in 131G. 5. The cable 182 passes over a second of the rollers 1'75, and progressively over the third and fourth rollers 175. The cable then terminates in a connection to the leaves 103 which are not shown in FIG. 5. A similar construction is utilized with respect to the cable 183, so that the cable 153 extends in the opposite direction over the rollers 175 and is shown as passing adjacent the hinge 14 and along the underside of the leaves 193 in a groove 197 therein. The cable 1%3 is then attached to the leaves 1% by means of a clamp assembly 198. It will be noted in FIG. 5 that the support member 184 has a groove 199 therein, within which the rollers 175 ride, so as to fix the support member 1% with respect to longitudinal movement about the support member.

Also shown in FIG. 5 is a partial section of the lock assemblies 1&5. The lock assemblies 1115 are pivotally connected to a flange m1 on the attaching plate 177 by means of a nut and bolt type pivot 2132. The flange 201 has a depression therein at 2133, within which a ball 2%, spring loaded by a spring 2115, rides to lock the lock assemblies in their upright position. A similar depression (not shown) is utilized to lock the lock assemblies in their horizontal position when the leaves are to be extended outwardly.

A section of the clamp assembly 135 is shown as including a clamp body 2111 attached to the frame 106 by a nut and bolt combination 211, so as to fix the clamp 210 in position with respect to the frame 1%; A clamp arm 212 is pivotally connected to the clamp body 2111 by means of an axle 213', and is spring loaded by a load spring 214 to assume the position shown. The clamp release bar 137 is shown as having a releasing cam 21.5 attached thereto, as is more clearly shown in FIG. 7. When the clamp assembly 135 is to be released, the releasing cam 215 rides against a camming surface 216 of the clamp arm 212, thus forcing the clamp arm 212 away from the adjacent clamp body portion so as to release the bracket 165.

FIGURE 6 is a side elevation, partially in section, illustrating the drive gear assembly 128 and slave drive assembly .130. A cable drum 220, previously referred to as attached to the second gear 181, is shown having cables 182 and 1 83 attached thereto. A similar drum is shown as included in the slave dnive assembly 1 30. The cables 182 and 1 83 are shown to be of a fixed overall length by being clamped to the torque transfer tube 129 by nut and bolt assemblies 221, which also function to attach the cable drums 221 to the torque transfer tube 129. In addition, the structure of the rollers 175 utilized to guide the cables 132 and 183 through the slot 199 is shown. The rollers 175 me disposed about axles 176, so as to be freely rotatable. Since the positioning plate 177 and rollers 175 are connected to the frame, bearings 223 are utilized to permit the rotation of the torque transfer tube and a sleeve 224 housing the drive shaft 127, so as to permit its rotation.

The handle 126 has a recess 225 which encloses the end of the drive shaft 127. A dowel 226 engages the handle 126 and extends through an aperture 227 in the drive shaft 127. A loading spring 228 is positioned between the dowel 226 and a threaded plug 229 which has a stud 2319 which engages an aperture 231 in the handle 126. The spring loading of the handle causes the handle to remain in the position shown so that the drive shaft 127 may be rotated by the handle 126. The handle may be swung out of the way by pulling the handle against the pressure of the spring 228. When the aperture 231 clears the stud 230, the dowel 226 acts as a pivot to permit the handle 126 to swing downwardly out of position, so as to not constitute a nuisance because of its extension beyond the frame 196.

The drive shaft 127 is supported from the frame 106 by a bracket 233, which holds the drive shaft 127 by means of a bearing 234 and a washer 235. A dowel 23-6 holds the drive shaft in position.

FIGURE 7 is a sectional view taken along lines 7-7 of FIG. 5, illustrating the construction of the attaching clamp 13- 5. It will be seen that the cam 215 is held in position by means 01 a pin 24 1, which extends through the release rod 137. The spring 21-4 is shown as disposed about the axle 213. The camming surface 216 is shown in section. A pair of apertures 242 are utilized in conjunction with the nut and bolt assemblies 121 (not shown, see FIG. 5) to attach the clamp body 210 to the frame 106.

The bracket 165 is seen to be U-shaped, the central portion engaging the attaching clamp 165. The bracket 165 has apertures in the ends thereof, through which the bolts 166 extend to attach the bracket 165 to the mattress support surface. For example, frame 161} (see FIG. 4).

Referring now to FIG. 8, there is shown a sectional view of the transfer frame 101, to illustrate the means by which these frames are connected together. It will be noted that by rotating the crank 117, the extension 115 is moved in position with respect to the adjacent vertical portion of the frame 107. The extension 115 is pivotally connected at 111 to the arm 108, and thus the movement of the extension 115 is translated to a raising or lowering of the arm 108. Since the arm 108 is pivotally connected to the frame 1116, this movement is translated as a raising and lowering of the frame 106.

As shown, the frame 106 is in a horizontal disposition. If it is desired to change the inclination of the frame 106 from this horizontal disposition, the crank 11-8 is rotated, so as to move the arm 119 with respect to the adjacent vertical leg portion of the frame 107. Since the arm 119 is pivotally connected to the arms 1119 at the pivot 1113, this movement causes a movement of the pivot 113 along the frame 107. A movement of the pivot 113 towards the pivot 111 causes a depression of the frame 106 at the pivot point 112. Correspondingly, the movement of the pivot 113 away from the pivot point 11-1 causes a raising of the frame 106 at the pivot point 112. Thus, the inclination of the frame 196 and, therefore, the support member 102 is selectable.- It will usually be desired to maintain the frame 106 in a level disposition, rather than being inclined to provide the just described inclined Trendelenberg or reverse Trendelenberg positions. In order to facilitate the maintenance of the horizontal or level disposition, a lock assembly 250 is provided and is shown in more detail in FIGS. 9 and 10.

In FIG. 9, a plan view, partially in section, of the frames 1116 and 10-7 is shown. The frame 166 has been broken away as appropriate in order to illustrate the construction of the frame 107. It will be noted that the cranks 117 and 118 are attached to the frame 107 by means of cross members 261} and 261, respectively. The cross member 261 has an attaching lock 262 attached thereto, which is utilized to hold the crank 118 in place. Supporting rods 265 are connected between the cross member 260 and the frame 107, in order to provide additional rigidity for the frame. Pivot arm 270 is connected between the extension 115 and the arm 1118, in order to provide additional rigidity between these arms. The pivots 110, =1 11 and 112 have pivot arms 270, 2711 and 272, respectively, extending between the opposite sides of the frames associated therewith, about which the pivoting occurs. The structures by which the pivot arms 270, 27 1 and 272 are connected to the frames associated therewith is illustrate-d by the portion broken away from the frame 106 at the pivot 116, and includes a pivot arm extension 275, which rides within a sleeve 276, extending into the frame 106. A pivot mounting block 277 is utilized to hold the sleeve 276 in position.

FIGURE 10 is a sectional View of the pivot assembly 251). The pivot assembly 250 includes a pivot arm 280, about which the arms 1119 and 1119 pivot (see FIG. 9). A slot-ted housing 29% is shown in section as having a slot formed between open faces 291 (only one face 291 being shown). The pivot arm 281) extends into the slot. An opposite closed face 292 has nut and bolt assemblies 293 extending therethrough, so as to attach the housing 290 to the frame 19-7. The pivot arm 280 terminates in a spring loaded detent mechanism 295. The spring loaded detent 295 includes a spring 296 held in compression in the pivot arm 2811 by means of a pin 2'97 extending therethrough. A detent block 298 holds the spring 296 within the pivot arm 280 and terminates in a detent surface 299. The detent surface 299 extends through an aperture 300 in the closed face 292 and into an aperture 301 in the frame 107. The aperture 391 is formed at such a point that, when the detent surface 299 extends therein, the pivot arm 280 is positioned so that the frame 106 is level. In order to release the detent surface 299 from the aperture 301, a detent release rod 302 extends through the frame 107, and terminates in a face 303, which abuts the aperture 391, so as to be selectively extendable therethrough. The detent release rod 392 terminates at one end in a ball 3%, for the convenience of the operator. In order to release the detent mechanism 295, the rod 302 is moved in the direction of the detent mechanism 295, so as to displace the detent surface 299 from the apertures 301. The crank 118 may be actuated to change the inclination of the frame 106 as desired.

In FIG. 11, an alternate embodiment for the lateral displacement of the support member 102 is illustrated. In the embodiment of FIG. 11, the groove 199 of FIG. 5 has been replaced by a slot 3-10, which has gear teeth molded therein. The drive shaft 127 has gears 311 attached thereto by pins 312. The gears 311 engage the gear teeth in the slot 310 directly. Upon rotation of the drive shaft 127, the lateral displacement of the support member 1112 is accomplished. In order to prevent the support member 102 from being lifted off of the transfer apparatus, the support member 102 has a cavity 315 molded therein, which engages a finger 3'16, separated from the drive shaft 127 by a bearing 318, and attached to the trans-fer apparatus by means of an attaching plate 319, so as to be fixed with respect thereto.

The invention claimed is:

1. Support apparatus comprising:

a. patient transfer mechanism including (1) a wheeled base,

(2) a rectangular support frame,

(3) attaching means connected between the base and frame so that the support frame is disposed over the base,

(4) a rigid generally rectangular mattress support member foldable between :a flat disposition and a U-shaped disposition,

(5) coupling means for coupling the mattress sup port member to the mattress support frame so that the mattress support member is longitudinally fixed and laterally displaceable with respect to the support frame, and

(6) mattress support lateral displacement means connected between the mattress support member and the support frame, including (a) a rotatable crank member, and (b) means connecting the rotatable crank member between the frame and the mattress support member so that rotation of the rotatable crank member iateral ly displaces the mattress support member, the magnitude and direction of said lateral displacement being determined by the amount and direction of rotation of said rotatable crank member,

b. a pair of clamp members attached to one side of the frame and spaced from each other, said clamp member being adapted to mate with complementary clamp receiving members attached to a bed frame so as to couple the bed frame together,

0. resilient mattress means, and

d. means for selectively connecting said mattress means to the support frame including (1) a pair of grommets attached to the bottom of one side .of the mattress means in spaced relation to each other, and

(2) a pair of grommet connecting means (a) attached one to either end of the support frame so as to be disposed above the mattress support member, and (b) operable, when so attached, to hold the mattress means, when supported on the bed frame, in spaced relation to said support frame, so that the lateral displacement of the mattress support member in direction of the mattress means causes the mattress support member to slide under and separate the mattress means from the bed frame.

2. Apparatus according to claim 1 and in which the attaching means connected between the base and frame includes a first attaching member, a first fixed pivotal connection between the first attaching member and the base, a second fixed pivotal connection between the first attaching member and the support frame, a second attaching member, a third fixed pivotal connection between the second attaching member and the support frame, a movable pivotal connection between the second attaching member and the base, means connected between the base and the second attaching member for selectively displacing the movable pivotal connection longitudinally along the base, and means connected between the base and the first attaching member for selectively pivoting the first attaching member about the first pivotal connection.

3. Apparatus according to claim 1 and in which the mattress support lateral displacement means includes a cable drum to which the rotatable crank member is attached, first and second cables wound in opposite direc tions about said cable drum, rotatable first cable guide means attached to the support frame along one side thereof, rotatable second cable guide means attached to the support frame so as to be disposed opposite the first cable guide means, first cable attaching means attached to the mattress support member transverse from the first cable guide means, and second cable attaching means attached to the mattress support member transverse from said second cable guide means, said first and second cables passing from the cable drum about their respective guide means and terminating at their respective attaching means, whereby rotation of the crank rotates the cable drum so as to wind one of said cables and unwind the other cable about the cable drum to laterally displace the mattress support member.

4. Apparatus according to claim 1 and in which the complementary clamp receiving members attached to the bed frame comprise outwardly extending U-shaped members and in which the clamp members each include a clamp body extending outwardly from the support frame, a release arm pivotally attached to the clamp body, spring bias means connected between the release arm and clamp body to urge the release arm into a closed position against the clamp body, in which position the release arm encloses a portion of said U-shaped member to hold said member against the clamp body, a icamming surf-ace formed on said release arm, and a releasing cam connected to the clamp body so as to be transversely movable with respect to the release arm between a clamped position and a clamp release position, the releasing cam engaging the carnmi-ng surface of the releasing arm during movement from the clamp position to the clamp release position to pivot the releasing arm against the urging of the bias spring so as to move the releasing arm away from the U-shaped member, thereby releasing the U-shaped member from the clamp, and including a clamp release rod to which each of said releasing cams are attached, said rod extending to the end of the support frame at which the crank member is disposed, so as to be operable to simultaneously release both clamp members by longitudinal movement of the rod to move the respective releasing cams from their clamped position to their clamp release position.

5. Adjustable support apparatus comprising a wheeled base, a rectangular support frame disposed over the base, means pivotally attaching the base to the support frame including a first attaching member, a first fixed pivotal connection between the first attaching member and the base, a second fixed pivotal connection between the first attaching member and the support frame, a second attaching member, a third fixed pivotal connection between the second attaching member and the support frame, a movable pivotal connection between the second attaching member and the base, means connected between the base and the second attaching member for selectively displacing the movable pivotal connection longitudinally along the Phase, means connected between the base and the first attaching member for selectively pivoting the first attaching member about the first pivotal connect-ion, coupling means for selectively connecting the support frame to an adjacent mating structure, a substantially rectangular support member disposed over the support frame so as to be supported thereby, said support member including a first leaf, first leaf attaching means connecting the first leaf to one side of the support member, a second leaf, and second leaf attaching means connecting the second leaf to the opposite side of the support member, so that the first and second leaves may be swung between a horizontal position and an upturned vertical position, means connected to the support frame for selectively locking the leaves in the upturned vertical position, and support member transverse movement means connected between the support member and the support frame and operable to selectively move the support member transversely with respect to the support frame.

6. Apparatus as described in claim 5 in which the support member transverse movement means includes a drive shaft and handle rotatably connected to the support frame, drive means connected to the support member, and a drive gear in engagement with the drive shaft and the drive means.

7. Apparatus for coupling a mobile frame to a bed frame comprising a pair of clamp receiving members attached to the bed frame along one side thereof in a spaced disposition, said receiving members being of an outwardly extending U-shaped configuration, and a pair of complementary clamp members attached along one side of the movable frame in a disposition complementary to the disposition of the clamp receiving members, said clamp members each including a clamp body extending outwardly from the mobile frame, a release arm pivotally attached to the clamp body, spring bias means connected between the release arm and clamp body to urge the release arm into a closed position against the clamp body, in which position the release arm encloses a portion of said U-shaped member to hold said member against the clamp body, a camming surface formed on said release arm, and a releasing cam connected to the clamp body so as to be transversely movable with respect to the release arm between va clamped position and a clamp release position, the releasing cam engaging the camming surface of the releasing arm during movement from the clamp'position to the clamp release position to pivot the releasing arm against the urging of the bias spring so as to move the releasing arm away from the U-shaped member, thereby releasing the U-shaped member from the clamp, and including a clamp release rod to which each of said releasing cams are attached, said rod extending to one end of the mobile frame so as to be operable to simultaneously release both clamp members by longitudinal movement of the rod to move the respective releasing cams from their clamped position to their clamp release position.

References Cited in the file of this patent UNITED STATES PATENTS Gil le land Oct. 31, 19-50 Dean Aug. 28, 1951 (Sanders et al Jan. 20, 1953 Gilleland Mar. 10, 1953 Butler Jan. 12, 1954 'Hollstein Apr. 26, 1955 Reichert et a1 Sept. 29, 1959 

5. ADJUSTABLE SUPPORT APPARATUS COMPRISING A WHEELED BASE, A RECTANGULAR SUPPORT FRAME DISPOSED OVER THE BASE, MEANS PIVOTALLY ATTACHING THE BASE TO THE SUPPORT FRAME INCLUDING A FIRST ATTACHING MEMBER, A FIRST FIXED PIVOTAL CONNECTION BETWEEN THE FIRST ATTACHING MEMBER AND THE BASE, A SECOND FIXED PIVOTAL CONNECTION BETWEEN THE FIRST ATTACHING MEMBER AND THE SUPPORT FRAME, A SECOND ATTACHING MEMBER, A THIRD FIXED PIVOTAL CONNECTION BETWEEN THE SECOND ATTACHING MEMBER AND THE SUPPORT FRAME, A MOVABLE PIVOTAL CONNECTION BETWEEN THE SECOND ATTACHING MEMBER AND THE BASE, MEANS CONNECTED BETWEEN THE BASE AND THE SECOND ATTACHING MEMBER FOR SELECTIVELY DISPLACING THE MOVABLE PIVOTAL CONNECTION LONGITUDINALLY ALONG THE BASE, MEANS CONNECTED BETWEEN THE BASE AND THE FIRST ATTACHING MEMBER FOR SELECTIVELY PIVOTING THE FIRST ATTACHING MEMBER ABOUT THE FIRST PIVOTAL CONNECTION, COUPLING MEANS FOR SELECTIVELY CONNECTING THE SUPPORT FRAME TO AN ADJACENT MATING STRUCTURE, A SUBSTANTIALLY RECTANGULAR SUPPORT MEMBER DISPOSED OVER THE SUPPORT FRAME SO AS TO BE SUPPORTED THEREBY, SAID SUPPORT MEMBER INCLUDING A FIRST LEAF, FIRST LEAF ATTACHING MEANS CONNECTING THE FIRST LEAF TO ONE SIDE OF THE SUPPORT MEMBER, A SECOND LEAF, AND SECOND LEAF ATTACHING MEANS CONNECTING THE SECOND LEAF TO THE OPPOSITE SIDE OF THE SUPPORT MEMBER, SO THAT THE FIRST AND SECOND LEAVES MAY BE SWUNG BETWEEN A HORIZONTAL POSITION AND AN UPTURNED VERTICAL POSITION, MEANS CONNECTED TO THE SUPPORT FRAME FOR SELECTIVELY LOCKING THE LEAVES IN THE UPTURNED VERTICAL POSITION, AND SUPPORT MEMBER TRANSVERSE MOVEMENT MEANS CONNECTED BETWEEN THE SUPPORT MEMBER AND THE SUPPORT FRAME AND OPERABLE TO SELECTIVELY MOVE THE SUPPORT MEMBER TRANSVERSELY WITH RESPECT TO THE SUPPORT FRAME. 